Human chorionic gonadotropin and gastric emptying in pregnancy

Human chorionic gonadotropin and gastric emptying in pregnancy Nausea and vomiting in pregnancy (NVP) is the most common phenomenon during the first trimester of pregnancy and it results from a prolongation of gastrointestinal transit. It has been hypothesised that Increased human chorionic gonadotropin (hCG) is the most likely cause of NVP. Cholecystokinin (CCK), a 33 amino acid peptide inhibits gastric emptying in animals and humans but has also been reported to stimulate colonic transit in vivo.

Seow et al. conducted a study was to investigate the effects of hCG on gastric emptying and gastrointestinal transit in ovariectomized (Ovx) rats and to clarify the role of CCK and its receptors in regulating the effect of hCG on gastrointestinal transit.

In this study, they show that hCG treatment resulted in dose-dependent inhibition of gastric emptying in Ovx rats but had no effect on intestinal transit. Furthermore, hCG increased plasma CCK concentrations in a dose-dependent manner in Ovx rats, and gastric emptying showed a significantly negative correlation with CCK concentrations. This showed that, in Ovx rats, hCG inhibited gastric emptying, but not intestinal transit, through a mechanism involving increased secretion of CCK, a finding that has not been previously described. These results might explain the mechanism of the delay in gastric emptying time in pregnant women during the first trimester of pregnancy.

Read full article at Seow et al. (2013) Journal of Endocrinology 216 307-314 DOI: 10.1530/JOE-12-0421